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Identifying unknown e. coli - (Nov/02/2015 )

The photo is a sample of lab grown DH5-alpha e. coli. There are some long strings that appear to be cells which have not divided completely. Does anyone recognise this mutation? I'd appreciate some information. 

Thanks!

 

Attached Image

-Sarah Winkler-

The image is practically unviewable. But the cell morphology is very common in lab strains, especially ones that are undergoing stress of some kind. Overexpression of proteins, or presence of highly expressing plasmids often cause this behavior. If you are using E. coli as a method of DNA or protein production, then this should not be a problem. If you are investigating the cell physiology, then you probably don't want to be using a lab strain such as DH5 alpha in any case. The more "robust" E. coli strains such as MG1655 will look and behave much healthier under your microscope.

-phage434-

are you sure those aren't contaminating fibers?

-mdfenko-

mdfenko on Mon Nov 2 13:47:26 2015 said:

are you sure those aren't contaminating fibers?

Indeed.

 

Those very long strings, do not seem to be cells. Unless, but seems far fatched, they are dividing cells that somehow stayed stuck to eachother, but hard to tell on the picture.

-pito-